Despite the metaphor, current virtual desktops bear little resemblance to the look or feel of real world desktops. A workspace in the physical world typically has piles of documents, binders and other objects arranged in a way that provides considerable subtle information to the owner. For example, items are often casually placed but their spatial position and orientation are usually meaningful. Closer items can indicate urgency, and piles of items are “automatically” ordered chronologically because new items are typically placed on top. This casual organization, prevalent in the real world, differs greatly from the GUI desktop which forces users to immediately file their documents into a rigid hierarchy. Filing typically requires more effort than piling and has been shown to have other negative effects such as encouraging premature storage of low value documents, or retaining useless documents because of the effort that went into filing them.
There has been significant research and development in this area. Office worker organizational behaviour studies have identified two general paper organization strategies: ‘piling’ and ‘filing’. It has also been found that categorizing and filing items was cognitively difficult. It has been noted that virtual desktops should provide untitled piles that support deferred classification as well as titled, logically arranged files. Further, it has been postulated that ‘electronic piles’ should make the use of computers more natural.
Piling as an organizing strategy has several advantages over filing. (Whittaker, S. & Hirschberg, J. (2001), The character, value, and management of personal paper archives, ACM Trans on CHI, 8(2), p. 150-170.) Piling is lightweight, casual, involves less overhead, and is easier to maintain than filing. Piles serve as visual reminders and increased availability of recent information. Pilers more frequently access their piles than filers accessed their file archives. Pilers archives may also be smaller, which can be attributed to piled information being easier to discard. Filers reluctantly discard information due to the effort put into initially filing it. Filers also prematurely filed documents later deemed to be of little or no value. In addition, sometimes more than one filing category applies, or an existing category is forgotten and a new one created. On the other hand, piling did not scale well and information was difficult to find once the number of piles grew large. Taken to excess, piling can take over every surface in an office. Despite the advantages of piling, there remains little technological support for piling in today's GUI desktops.
The pile metaphor has been explored in a prototype. (Mander, R., Salomon, G., & Wong, Y. (1992), A “pile” metaphor for supporting casual organization of information, CHI, p. 260-269.) The prototype was based on a user-centered iterative design process. Gestures and interaction techniques were introduced (sometimes modal) for browsing and manipulating piles and facilitating ‘casual organization’ on the desktop.
Previous work has also looked at piles in different contexts. DiGioia et al. used a pile visualization to aid ‘social navigation’ and security. (DiGioia, P. & Dourish, P. (2005), Social navigation as a model for usable security, ACM SOUPS, p. 101-108.) Ruffled piles were used to indicate information a group of users frequently accessed. To remove documents or piles from public access they could be moved to a ‘filing cabinet’.
DynaPad™'s “open” pile representation laid out entire collections of photos side-byside on a zoomable Pad++™ based workspace. (Bauer, D., Fastrez, P., & Hollan, J. (2004), Computationally-enriched “piles” for managing digital photo collections, IEEE VLHCC, p. 193-195; Bederson, B. & Hollan, J. (1994), Pad++: a zooming graphical interface for exploring alternate interface physics, UIST, p. 17-26.) This representation avoids occlusion of stacked items with each other, but results in higher visual load and greater screen real-estate requirements. The latter issue is mitigated because of infinite canvas. “Open” piles also aim to enhance remindability through visibility of all sub-objects, although this diminishes when the workspace is zoomed out and thumbnails become small. The alternative stack representation is in the spirit of familiar real-world piles and does not require a zoomable interface. The linearly ordered piles support fluid sorting and re-ordering in place without the need for additional tools.
Recent physically-inspired GUI designs rethink windows as paper stacked in piles. Windows can be freeform peeled like real pieces of paper with a robust algorithm. Peeling and re-orientation allows viewing of occluded windows below. (Beaudouin-Lafon, M. (2001), Novel interaction techniques for overlapping windows, UIST, p. 152-154.)
Denoue et al. disclosed using real-time simulated cloth texture-mapped as fliers and pinned up to virtual bulletin board that blow in the wind. (Denoue, L., Nelson, L., & Churchill, E. (2003), A fast, interactive 3D paper-flier metaphor for digital bulletin boards, UIST, p. 169-172.)
Tossing as a window moving technique has also been disclosed. (Yatani, K., Tamura, K., Hiroki, K., Sugimoto, M., & Hasizume, H. (2005), Toss-it: intuitive information transfer techniques for mobile devices, CHI Ext. Abs., p. 1881-1884; Streitz, N., Geiβler, J., Holmer, T., Konomi, S. i., Müller-Tomfelde, C., Reischl, W., Rexroth, P., Seitz, P., & Steinmetz, R. (1999), i-LAND: an interactive landscape for creativity and innovation, CHI, p. 120-127.)
The benefits of spatially based organization have also been shown. Leveraging spatial memory in organizing webpage thumbnails on a perspective 2½D plane has showed improved user performance against text-based webpage bookmarks. (Robertson, G., Czerwinski, M., Larson, K., Robbins, D., Thiel, D., & van Dantzich, M. (1998), Data mountain: Using spatial memory for document management, UIST, p. 153-162.)
Recent investigations into pen-based computing have broken away from traditional point-and-click interfaces to techniques that are easier accomplished with the pen such as goal crossing. (Accot, J. & Zhai, S. (2002), More than dotting the i's—foundations for crossing-based interfaces, CHI, p. 73-80.)
In addition to the academic developments and disclosures, there are some notable patents in this field. U.S. Pat. No. 5,303,388 to Kreitman et al. describes manipulable icons that are represented as three-dimensional objects with different data on each side that a user can manipulate. A user is therefore required to manually rotate icons to view the additional information. In addition, representing information on every side of the object constrain the potential shape of the object in order to maintain readability of each of the sides. Representing information on each side of an icon can also waste screen real estate as there may not be any relevant information to display for particular objects.
U.S. Pat. Nos. 5,838,326 and 5,847,709 to Card et al. describes a “flick gesture” to move documents around to different components of an electronic workspace. The system is limited because it allows the documents to be tossed to finite areas only. “Flick gestures” in the cardinal directions are mapped to one-to-one onto specific workspace areas. This limits the expressive range and number of places documents may be moved with this technique. As well, the use of time-based gesture detection has inherent problems in recognition resulting in inaccuracy and false positives.
In U.S. Pat. No. 6,677,965 to Ullmann et al. a virtual rubber-band is created between the cursor and a GUI control such as a slider or scrollbar. This provides visual feedback and variable rate control of the slider dependent on how the cursor is moved from the GUI control. The technique is only applied to discrete 1-dimensional positioning of GUI controls.
U.S. Pat. No. 6,915,489 to Gargi discloses a system that stacks images diagonally and allows moving the mouse in a direction to browse them at a disjoint screen location. This diagonal arrangement with disjoint secondary-image requires a large amount of screen real estate and does not scale well to a very large number of items. The diagonal layout also does not efficiently use the space to the top-right or bottom-left of the diagonal arrangement of images. Also, this stacking technique occludes much of the images with the ones on top of it.
U.S. Pat. Nos. 6,928,621, 5,583,984 and 6,307,545 to Conrad et al. describe a “spring loaded folders” technique. Moving the mouse and pausing over an “enclosure” opens its window temporarily while the mouse is down. The new window may occlude items behind it, and browsing will require moving the mouse cursor outside the layers of sprung open windows, and then reacquisition of potentially occluded other folders.
U.S. Pat. No. 6,907,580 to Michelman et al. describes a moveable user interface element containing displayed options for further manipulation of a selected object. However, user interface elements are triggered by point-and-click interaction, which breaks user flow and is not continuous.
In addition, U.S. Pat. Nos. 6,613,101 and 6,243,724 to Mander et al. discloses a mode-based piling approach to document organization. Gestures and interaction techniques were disclosed for browsing and manipulating piles and “casual organization” on a desktop. However, mode-based interaction techniques are known to be problematic as users often forget what mode they are in or that they need to switch. In addition, their approach uses idiosyncratic gestures which are prone to imperfect recognition and requiring memorization are used to trigger interaction. Also, some of the techniques disclosed are in isolation and not integrated with each other. For instance, sorting piles required a special mode with its own interface inside a dialog box, and is not integrated with the main display.
In light of the foregoing, what is needed is an improved method, system and computer program for organizing and visualizing display objects within a virtual environment. In particular, what is needed is a method, system and computer program that enables easy selection of multiple objects, distinguishing objects, enhanced interaction of objects, enhanced organization of objects, enhanced visualization of object properties and meta-data as well as enhanced browsing techniques. What is further needed is a method, system and computer program product having effective and coherent interaction and visualization techniques for virtual environment organization.